From a04dc87db140ddfb86008f424b8c4b2b6eeaa4cf Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 31 May 2012 11:20:02 -0400
Subject: [PATCH] Improve comment for GetStableLatestTransactionId().

---
 src/backend/access/transam/xact.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 5ae46dee9b5..49c14cb64c0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -393,8 +393,10 @@ GetCurrentTransactionIdIfAny(void)
 /*
  *	GetStableLatestTransactionId
  *
- * Get the XID once and then return same value for rest of transaction.
- * Acts as a useful reference point for maintenance tasks.
+ * Get the transaction's XID if it has one, else read the next-to-be-assigned
+ * XID.  Once we have a value, return that same value for the remainder of the
+ * current transaction.  This is meant to provide the reference point for the
+ * age(xid) function, but might be useful for other maintenance tasks as well.
  */
 TransactionId
 GetStableLatestTransactionId(void)
-- 
GitLab